Forced Induction - is there a long term reliability problem for the 86/BRZ
 

An interesting quote from this months (October 2012) MOTOR magazine from Australian rally champion Rick Bates;-

Bates had a sneaky drive of the 86 before its local launch and discussions with chief engineer Tetsuya Tada were revealing " I asked him about tuning and he said there are some internal engine parts that won't take (forced induction). So I'll be interested to see how reliable some of these ones making big power will be down the track"

Makes me somewhat wary, but keen to see the various tuners responses.

tuners have this car pushing over 400 HP on stock internals and they have done hundreds of dyno pulls and countless drags and street runs.... I think that is the equivalent of many years of a normal persons use by now.

Interesting quote there. Only time will tell what kind of stress the engine will be put through with the stock internals and forced induction.

I said to myself "well duh!"

How many non-factory turbo cars are built for a turbo? He just gave the engineers answer of "we didn't engineer it that way."

What it was built to do and what it can do are not always the same thing.

"turbo" means different things

low blow at 8 psi is differnet to stuffing it full of 20 psu

I suspect this was his point, how much is too much though?

man says no! period! pretty plain i would say!
chief engineer! he should know! guess that means ya put a "blower"
on it at your own peril!..kiss your warranty goodbye if it blows up!
just sayin'

I must admiy at the moment there are 80 people who havent got very far with their car stock....

One poor guy had only 4 miles on the clock and straight back to the shop. Hopefully they will find the fault soon and have a fix. I think I will let the dust settle before I start "moding" the 86 too far.

I am sure that from an engineer's perspective this car should not have forced induction in stock form.

If they did not factor the higher loading on various components when they were developed, they will not condone going beyond intended use on a stock spec car.

It is not as though the car would have been "over engineered" with cost being a consideration. Stronger components almost always cost more.

That said, perhaps a component designed for say, 100,000 km such as a clutch plate, might work just fine and not "blow up", but rather have a shortened service life.

My concern is for internals whose failures would be "catastrophic" to the engine.

Again, I get the feeling that it's wise to stay conservative with the boost and hope there are no unpleasant surprises.

BTW I know squat about mechanicals. I do, however, work on a daily basis with engineers and have seen first hand they usually won't over engineer anything where there is cost constraint.

Crawford tore this engine apart and said some components were built pretty well. Of course there is always a risk when boosting a car that was not engineered from the factory to take force induction but they have to say that for many reasons. I would put money on it that a well tuned, well taken care of FRS/BRZ that has a modest boost level, 6-10 psi could last over 100k miles. Take a look at the early Mazdaspeed Protege. I owned one. That had a stock Protege engine that was never meant for boost, but Mazda slapped on a Callaway designed turbo kit running 6.5 lbs of boost. I had my tuned at 10psi and drove it daily (including winters) for over 5 years, and 80k miles. I NEVER had an issue. And those engines are horribly weak. The FA20 has already been proven to take over 400whp. I don't see it being an issue at all.

Engineers will always take the safest path when it comes to this sorta thing. The chief engineer had very little to do with this engine other than saying "that works for me" I'm sure.

This is a Subaru engine. The cost to retool an entire machining facility to run this engine means that it's going to be used in several applications. The engine was designed and built with that in mind.
I'd be willing to bet there will be small variances in crankshaft stiffness, main bearing bolt strength, head gasket durability, piston thickness, and piston pin hardness between a NA and turba FA20. Then again there may well be no differance at all.

I hope everyone understand how public relations work. The Chief Engineer CANNOT say the car will hold boost. IF he says yes, first motor that blows up is bad PR. He has no incentive to say otherwise.

In this case, it is better for him to be "proven wrong" by the tuning community.

Nothing to see here guys/gals, move on.

Hundreds of dyno pull where you get your information from? please

Don at Accelerated Performance for sure has hundreds of dyno pulls. He has also been daily driving the shop BRZ with over 450whp, 18-20psi of boost, and a few 1/4 mile runs including an 11.3 at 130+.